下呼吸道及肺癌内菌群与肺癌发生发展的关系及其临床应用

由于16S rRNA测序技术的发展，长期以来被认为是不存在的下呼吸道菌群也逐步被揭示出来。这些微生物与疾病（如肿瘤）的相关性是近年来的研究热点。由于肿瘤周围环境中的菌群会进入肿瘤内部，研究者们也开始关注肿瘤内菌群的生物学行为以及其与肿瘤的相互作用。在这篇综述中，我们展示了下呼吸道菌群的特点，并总结了近年来关于这些菌群与肺癌关系的相关研究成果。同时，我们也对肿瘤内菌群的基本特征进行整理，并着重阐述肺癌内菌群的特点及其与肺癌发生、发展的关系。最后，我们综述了下呼吸道和肺癌内菌群在临床上的转化应用方向，并汇总了样本采集、测序和控制污染的要点，希望为肿瘤的早筛和治疗提供新的思路。

2. Compared with squamous cell carcinoma, tissues of adenocarcinoma had increased relative abundance of Thermus and decreased relative abundance of Ralstonia.

(non-tumor adjacent tissue) (from databases)
1.There were distinct microbial populations within squamous cell carcinoma and adenocarcinoma.
2. Among squamous cell carcinoma, Acidovorax was more abundant in smokers and patients with TP53 mutation.
Peters BA, et al.
2. Families Koribacteraceae and Lachnospiraceae in lung cancer tissue were associated with reduced RFS and DFS.

(normal tissue)
1.The bacterial load of lung cancer was at an intermediate level among pan-cancer.
2. Compared with other tumor types, metabolic pathways that degrade chemicals in cigarettes were enriched in the bacterial community of lung cancer.
3. Several metabolic pathways related to the biosynthesis of metabolites that can be used by plants were enriched in bacteria of lung cancer of smokers.
Wong LM, et al.

(adjacent normal tissue) (from databases)
Age and gender were important factors affecting the bacterial composition in lung cancer.

(adjacent non-tumor lung tissue)
Due to the low abundance of bacteria in tumors and adjacent tissue, the results were susceptible to contamination and the authors did not compare the bacteria in these two types of samples.
Leblond N, et al.

(healthy adjacent tissue)
Enteric, potentially pathogenic and pro-inflammatory bacteria were more frequently found in cancer than healthy tissue.
Leng Q, et al.

(noncancerous lung tissue)
Compared with noncancerous lung tissues, Acidovorax was overrepresented in squamous cell carcinoma tissues and Capnocytophaga DNA was enriched in adenocarcinoma tissues.
Rolle A, et al.
2022 [18] 12 (lung tumor)+ 12 (adjacent normal region) 1.In tumor microenvironment, bacterial burden was significantly higher in tumor cells compared with other types of cells.
2. Genes involved in the Wnt/β-catenin, hypoxia, and angiogenesis pathways showed a strong positive correlation with bacterial burden.